Since their inception, power tools have provided craftsman with improved performance and ease of use. In more recent years, advancements in portable power technology have lead to incorporating the improved performance provided by a power tool into a handheld and often times, cordless configuration. These handheld power tools have provided increased flexibility and freedom of use by operators as well as increased efficiency by craftsman. A handheld power tool generally includes a handle mechanism, a trigger switch, a tool head, and a motor capable of moving the tool head in a desired direction.
To further increase ease of use and flexibility, some handheld power tools have advanced so as to permit interchangeability of the tool head. By permitting interchangeability, the same handle mechanism and motor can be used to operate different types of tool heads, such as a drill or driver, a circular saw, a sander, or a jigsaw. While this interchangeability provides convenience to the user, it also introduces the risk of permitting undesirable movement of the tool head, which can lead to serious injury of the tool operator, damage to the power tool, or damage to the surface on which the tool is operating. That is, certain tools heads such as a sander, jigsaw or circular saw are preferably not operated in a reverse direction.